Freshness is part of the data model

Keep the clocks separate#

A report may describe an earlier condition, arrive later, and be published later still. Re-fetching that record does not make the underlying observation new.

Observed / reported

When the condition was described. First and latest report times can differ.

Published

When WOUT made the record available. This is a publication fact, not an observation time.

Expires

When the record stops qualifying for the current view.

Snapshot

When this analysis was calculated. Upstream data can be cached for up to two minutes.

Different questions need different windows#

Signal expiration is category-specific. Short-lived local conditions can use windows measured in hours, while other categories can remain visible longer. The dashboard uses the actual expiration attached to each public record. The web news assistant uses published news from the past 48 hours. The security figure uses a separate rolling 24-hour definition.

These windows are not interchangeable. This analysis checks each public event’s actual expiration rather than assuming that every category has the same lifetime.

Expiration reduces stale presentation#

Expiration prevents an old report from remaining current indefinitely. It does not prove that the condition is still true until the exact expiration second. Confirmations, disputes, and resolution reports remain important.

The analysis page excludes expired records when calculating its current sample. When a source refresh fails, it reports that failure instead of interpreting an unavailable feed as zero activity.